Key Idea.
Section 1
Heating Increases Molecular Speed
Heating is the process of transferring energy into a substance. As molecules absorb this incoming energy, their kinetic energy increases.
This boost in energy causes them to move faster. If they gain enough speed, they may eventually break out of their rigid structures, leading to a phase change.
Section 2
Cooling Decreases Molecular Speed
Cooling is not the addition of "coldness," but the removal of energy. When energy is transferred out of a substance, the molecules lose kinetic energy.
As a result, they slow down. With less momentum, the molecules settle into more stable, orderly arrangements, potentially causing a gas to condense or a liquid to freeze.
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Section 1
Heating Increases Molecular Speed
Heating is the process of transferring energy into a substance. As molecules absorb this incoming energy, their kinetic energy increases.
This boost in energy causes them to move faster. If they gain enough speed, they may eventually break out of their rigid structures, leading to a phase change.
Section 2
Cooling Decreases Molecular Speed
Cooling is not the addition of "coldness," but the removal of energy. When energy is transferred out of a substance, the molecules lose kinetic energy.
As a result, they slow down. With less momentum, the molecules settle into more stable, orderly arrangements, potentially causing a gas to condense or a liquid to freeze.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter